Machine for assembling tubes in a heat exchanger

ABSTRACT

Machine for assembling automatically the tubes of a shell and tube type heat exchanger having many tubes of uniform length and a plurality of perforated baffle plates through which the tubes pass. A machine is provided having a tube holding fixture mounted on a work table. By means of opposing rods, selected quantities of tubes are transmitted successively from a tube supply to the fixture. Suitable controls are employed to complete one full tubular assembly during each operative cycle of the machine. The tubes are transmitted and assembled in the fixture in a single working plane. Following each deposit of tubes, the fixture is adjusted relative to the working plane preparatory to receiving the next quantity of tubes.

United States Patent 1191 Zifferer et al.

Feb. 5, 1974 1 MACHINE FOR ASSEMBLING TUBES IN A HEAT EXCHANGER Inventors: Morton F. Zllferer; Donald E.

Flinchbaugh, both of York, Pa.

Assignee: Mordo Company, Mt. Joy, Pa.

Filed: June 30, 1972 Appl. No.: 268,088

52 US. Cl 29/202 R, 29/1573 B lr 't liiffflflt" L '..'.'l"'!.'.' Z'Tf' 58 Field of Search 29/202 R, 202 D, 157,3 B,

29/1573 R, 208 D, 211 D, 203 D, 200 D References Cited UNITED STATES PATENTS 2,410,140 10/1946 Young 29/202 R 2,686,356 8/1954 Wolosianski 29/202 R Primary Examiner-Thomas H. Eager Attorney, Agent, or Firm-Robert B. Frailey 5 7 ABSTRACT Machine for assembling automatically the tubes of a shell and tube type heat exchanger having many tubes of uniform length and a plurality of perforated baffle plates through which the tubes pass. A machine is provided having a tube holding fixture mounted on a work table. By means of opposing rods, selected quantities of tubes are transmitted successively from a tube supply to the fixture. Suitable controls are employed to complete one full tubular assembly during each operative cycle of the machine. The tubes are transmitted and assembled in the fixture in a single working plane. Following each deposit of tubes, the fixture is adjusted relative to the working plane preparatory to receiving the next quantity of tubes.

Ll Claims, 1 7 Drawing Figures V Patented Feb. 5, 1974 7 Sheets-Sheet 1 Patented Feb. 5, 1974 '7 Sheets-Sheet 2 Patented Feb. 5, 1974 7 Sheets-Sheet 3 Patented Feb. 5, 1974 3,789,479

'7 Sheets-Sheet 4 @QQQQQ '7 Sheets-Sheet 5 Patented Feb. 5, 1974 Patented Feb. 5, 1974 '7 Sheets-Sheet 6 Patented Feb. 5, 1974 v 3,789,479

'7 Sheets-Sheet PHIL I JUL" WI L A MACHINE FOR ASSEMBLING TUBES IN A HEAT EXCHANGER SUMMARY OF THE INVENTION The primary object of this invention is to provide a new and improved machine for assembling quickly and automatically the many individual tubes incorporated into a shell and tube type of heat exchanger. Attempts have been made in the past to develop automated machines and methods to accomplish this, but these efforts, apparently, have been only partially successful, if successful at all. To a large extent, the assembling of tubes in conventional shell and tube heat exchangers still is being carried out manually.

This invention for the first time, so far as is presently known, successfully provides an automated machine for assembling, quickly and completely, the tubes in such a heat exchanger. The invention, in its preferred form, contemplates a tube holding fixture mounted on a work table having capacity for vertical and horizontal movement, a supply of tubes, means for advancing successively selected quantities of tubes from the supply to the fixture, such means preferably comprising individually controlled guide and insertion rods, means for adjusting the work table vertically and horizontally, following each transfer of tubes, to prepare the fixture for the next delivery of tubes and, finally, suitable control means to ensure that proper quantities of tubes are deposited in the fixture throughout the assembly cycle and to stop the operation upon completion of the assembly.

DESCRIPTION OF THE VIEWS OF THE DRAWING FIG. 1 is a fragmentary view in top plan of a preferred embodiment of the machine of this invention.

FIG. 2 is a fragmentary view in front elevation.

FIG. 3 is a schematic view in front elevation illustrating successive steps in the operation of the machine.

FIG. 4 is a fragmentary view in perspective of the tube holding fixture of the machine.

FIG. 5 is a fragmentary view in perspective ofa completed tube assembly for a heat exchanger produced by the machine.

FIG. 6 shows one of the baffle plates ofa tube assembly.

FIG. 7 is an enlarged, fragmentary view illustrating the manner in which a heat transfer tube is held by opposing rods as it is advanced to the tube holding fixture.

FIG. 8 is an enlarged, fragmentary view in section showing a preferred yielding connection between axially aligned rod sections.

FIG. 9 is an enlarged, fragmentary view looking in the direction of the arrows 9-9 of FIG. 2.

FIG. 10 is a fragmentary view in section looking in the direction of the arrows 10-10 of FIG. 9.

FIG. 11 is an enlarged, fragmentary illustration of the portion of FIG. 10 enclosed within the dot-dash lines designated 11.

FIG. 12 is an enlarged, fragmentary view in section looking in the direction of the arrows 12-12 of FIG. 10.

FIG. 13 is a fragmentary view in section looking in the direction of the arrows 13-13 of FIG. 2.

FIG. 14 is a fragmentary view in section looking in the direction of the arrows 14-14 of FIG. '13.

FIG. 15 is a fragmentary view in section looking in the direction of the arrows 15-15 of FIG. 14.

FIG. '16 is a fragmentary view of the control plate for the machine, looking in the direction of the arrows 16-16 of FIG. 13.

FIG. 17 is a fragmentary view in section looking in the direction of the arrows 17-17 of FIG. 13.

DETAILED DESCRIPTION OF THE INVENTION Referring first to FIG. 5 there is illustrated a typical tube assembly 16 for a heat exchanger assembled by the machine of this invention. The assembly comprises a plurality of individual, elongated tubes 18, only a few of which are illustrated, and a plurality of spaced, perforated baffle plates 19 of usual construction. As is clearly shown in FIG. 6, the truncated baffle plates 19 each have a plurality of parallel rows of apertures 51 (only some of which are illustrated). The apertures of adjacent rows are disposed in staggered relationship to each other. The number of apertures in'each row may vary widely.

Referring next to FIGS. 1, 2 and 3, the preferred machine of this invention may be conveniently divided into components A, B and C for ease of description. Component C includes a plurality of horizontally disposed guide rods 20, movable rod actuating means 21 for advancing a selected quantity of rods 20 past component B to a tube supply 31 in component A containing a quantity of tubes 18, a solenoid controlled double acting pneumatic cylinder 25 and a stationary detent mechanism 26 to prevent advancement of the nonselected rods.

Component A, in addition to tube supply 31, also includes a set of horizontally disposed insertion rods 32, movable rod actuating means 33 for advancing a selected quantity of rods 32 past the tube supply to component B and a solenoid controlled double acting pneumatic cylinder 30. The rods 20 and 32 are equal in number, and each individual rod 32 is aligned axially with a corresponding, opposing rod 20. Component A further includes a stationary detent mechanism 38 for preventing advance of the non-selected rods 32.

The tubes 18 in the tube supply 31 are disposed in successive horizontal layers, with their axes parallel to the axes of the rods 20 and 32. The horizontal axes of the tubes in the bottom layer are co-planar with the horizontal axes of rods 20 and 32. This is the working plane of the machine. Preferably, the number of tubes 18 in the bottom layer in hopper 31 equals the number of rods 20 (or 32), although the number of tubes could be greater or less than this number.

Component B includes a vertically and horizontally movable table 44 on which is mounted a tube holding fixture 45. As best shown in FIG. 4, fixture 45 includes a pair of axially spaced, transverse, vertical end plates 46, 47 and a plurality of intermediate transverse supports 48 for supporting vertically the baffle plates 19 of the tube assembly 16. Each of the intermediate supports 48 has its upper portion 480 hinged to provide for the insertion and removal of the baffle plates of the tube assemblies. The supports 48 sustain the baffle plates so that their rows of apertures 51 are horizontal.

' The end plates 46, 47 of fixture 45 are provided with a plurality of staggered apertures 52 formed into several horizontal. rows. The rows of apertures 52 of end plate 46 are co-planar with corresponding rows of apertures 52 of end plate 47 and with corresponding rows of apertures 51 of the upstanding intermediate baffle plates 19. Each row of apertures 51, 52 in the same horizontal plane contains the same number of apertures, and each aperture of each row is aligned axially with a corresponding aperture in each of its other coplanar rows. Thus, each aperture 52 in the fixture end plate 46 is co-axial with a corresponding aperture in each of the upstanding baffle plates 19 and in end plate 47.

The end plates 46, 47 are supported on table 44 so that their respective perforated areas are co-axial. Table 44 is vertically movable, both up and down, in successive increments, to bring the successive horizontal rows of staggered apertures 51, 52 into the working plane, previously described, of the machine.

As will be explained in more detail, selected rods 20 and 32 are advanced and retracted, respectively, by the action of the pneumatic cylinders 25, 30 transmitted through the rod actuating means 21, 33. FIG. 3 illustrates schematically various stages of operation of the machine. In stage 1, the first step in assembling tubes 18 in fixture 45 is illustrated. A selected quantity of rods 20 is advanced, by rod advancing means 21 and pneumatic cylinder 25, through the uppermost rows of axially aligned apertures 52, 51 in fixture 45 and baffle plates 19 to engage the proximate ends of the bottom layer of tubes 18 in hopper 31.

As best shown in FIG. 7, the forward ends 22 of the rods 20 preferably are of conical configuration, to permit limited entry of the rods into the open, proximate ends of the tubes 18. The forward ends 34 of rod 32 are of similar conical configuration, to permit their partial entry into the opposite, open ends of tubes 18. Hopper 31, at each end, is provided with openings 27, 37 to permit the entry of rods 20, 32, respectively, to engage the opposite ends of tubes 18, in the manner illustrated in FIG. 7.

Upon rods 20 reaching their maximum forward position, to engage tubes 18, the rod advancing means 21 strikes a limit switch 54, as illustrated in stage 2 of FIG. 3, to cause the solenoid (not shown) to close off further flow of compressed air to pneumatic cylinder 25. Activation of limit switch 54 also activates the solenoid controlled pneumatic cylinder 30 to advance those rods 32 which correspond to the selected rods 20. This same selected quantity of rods 32 is advanced by rod advancing means 33 and pneumatic cylinder 30 to the bottom layer of tubes 18 in the hopper to engage and hold the tubes in the manner illustrated in FIG. 7.

The rods 32 continue their advance, to push the corresponding rods 20 back beyond fixture 45 while, at the same time, advancing the selected tubes 18 to the fixture 45, as illustrated by stage 3 of FIG. 3. The tubes 18 are inserted by the rods 20, 32 through the axially aligned apertures 51, 52 in the uppermost row of apertures in end plates 46, 47 and baffles 19, to complete the assembly of the first layer of tubes. When the rods 32 have advanced sufficiently to position properly the tubes 18 in fixture 45, actuating means 33 strikes a limit switch 55. This activates the cylinder solenoids (not shown) to reverse the flow of compressed air to cylinders 25, 30 to retract the selected rods 20, 32 to their original positions, as illustrated by stage 4 of FIG. 3. The withdrawal of the rods 20, 32 completes the deposit of the first layer of tubes 18 in the fixture 45.

Thereupon, as illustrated in stage 4 of FIG. 3, table 44 is advanced upwardly an incremental distance sufficient to align the next succeeding co-planar rows of apertures 51, 52 in the working plane with the bottom layer of tubes 18 in hopper 31 and the rods 20, 32. As the table 44 elevates, it also is adjusted horizontally to align axially the staggered apertures in the next succeeding rows with the rods 20, 32 and the tubes 18 in hopper 31. This vertical and horizontal adjustment of table 44 occurs after rods 20, 32 have been restored to their normally retracted positions.

As rods 20 complete their return, rod actuating means 21 strikes a limit switch 57, as shown in stage 4 of FIG. 3, to shut off air to cylinder 25 and complete a circuit to activate suitable power control means to impart vertical and horizontal movement to table 44. Similarly, as rods 32 complete their return, rod actuating means 33 strikes a limit switch 56 to shut off air to cylinder 30.

In the particular embodiment shown (FIGS. 4, 5, 6), there are two tubes 18 in the uppermost row of tubes of the assembly 16, eight tubes in the second row, 1 l in the third, etc. However, the number of arrangement of tubes in any heat exchanger tube assembly, or any row thereof, is a matter of choice.

Following each deposit of a selected number of tubes 18 in the fixture 45, table 44 is advanced upwardly a distance sufficient to align each next succeeding coplanarrows of apertures 51, 52 in the working plane, until the last layer of tubes have been assembled, as illustrated by stage n of FIG. 3. At this juncture, the tube assembly is ready for removal from the fixture 45, preparatory to proceeding with the manufacture of the next assembly 16.

Referring back, for a moment, to FIG. 4, the newly completed tube assembly is removed from the fixture 45 by opening the hinged portions 48a of supports 48 and loosening bolts 49. The latter secure the end plates 46, 47 to end plate supports 50, and permit disengagement of the end plates from the opposite ends of the tubes 18 of the tube assembly.

In proceeding with the next tube assembly 16, the machine cycle is reversed, with the first layer of tubes 18 being deposited by rods 20, 32 in the lowermost apertures 51, 52 of baffle plates 19 and fixture end plates 46, 47. Following each deposit of tubes 18 in the fixture 45, table 44 is lowered an incremental distance sufficient to align the next succeeding co-planar rows of apertures 51, 52 in the working plane. Thus, as table 44 gradually is lowered, the next tube assembly is prepared, until finally the uppermost horizontal rows of apertures 51, 52 have returned to the working plane. After the final deposit of tubes in the fixture, the tube assembly is removed and the machine made ready for the next operative cycle.

Each time table 44 is advanced upwardly or downwardly, preparatory to the deposit of a new row of tubes 18, it is adjusted laterally to align properly the staggered apertures 51, 52 in the working plane with rods 20, 32 and the bottom layer of tubes 18 in hopper 31.

In order to compensate for differences in tube length, and to provide for suitable flexibility in the system, each guide rod 22 may be divided into two axially aligned components 201: and 20b as shown in FIG. 8. The forward component 20a has its rear end countersunk to provide a hole 60, which is intercepted by a transverse slot 61. The forward end 62 of the rear component20b is reduced in diameter, to engage telescopically within hole 60. A transverse pin 63, force fitted into reduced end 62, engages slot 61 to retain end 62 within hole 60. Preferably, the length of pin 63 approximates the outside diameter of rod portion 20a. A coil spring 64 urges the rod components 20a, 20b apart, when the rod 20 is at rest in its normally retracted position, as shown in FIGS. 1 and 8.

The insertion rods 32, of course, may be similarly constructed.

Referring now to FIGS. 9-12, a more detailed description of the structure and operation of the rod actuating means, rod detent mechanisms and pneumatic cylinders will be provided. Pneumatic cylinder 30 includes a reciprocal piston rod 70, the external end portion of which is in threaded engagement with a vertically dependent portion 71 of actuating means 33 (FIG. 10). As piston 70 is caused to advance and retract by the flow of compressed air to cylinder 30, it causes actuating means 33 similarly to advance and retract, as illustrated in FIGS. 3 and 9, along a pair of horizontally spaced guide rods 73. The latter are engaged slidably by annular bushings 74 disposed within spaced bores formed in the dependent portion 71 of actuating means 33.

Rod actuating means 33 is provided with a pair of vertically spaced, horizontal support members 76, 77 which extend tranversely of the rods 32. The members 76, 77 support a plurality of vertical, staggered air clamps 78, one of which is provided for each rod 32. Each air clamp is a small pneumatic cylinder individually connected by a suitable conduit 79 to a source of compressed air (not shown). A suitable solenoid controlled valve (not shown) is interposed in each conduit 79, to control individually the flow of compressed air to the air clamps 78.

Each air clamp 78 is provided with a retractable plunger 82, the distal end of which is adapted to engage within a notch 83 formed in the top of the rod 32 with which the air clamp is associated. A transverse guide bar 84 is disposed above rods 32 and is provided with a plurality of spaced, staggered bores, each for the reception of one of the plungers 82. The plungers 82 are engaged slidably within the guide bar bores, for engagement with, and retraction from, the notches 83 in the rods 32. Each plunger 82 is provided with a collar 85. A coil spring 86 is disposed around each plunger between the collar and the top of the guide bar 84. The springs 86 retract the plungers from the notches 83, when compressed air is exhausted from the air clamps 78. When the solenoid controlled valve (not shown) for any particular conduit 79 is opened, permitting com- 4 pressed air to pass to the air clamp 78, the plunger 82 advances against the force of the spring 86 to engage with notch 83, and thereby clamp its rod 32 to the rod actuating means 33. When this occurs, all rods 32 thus clamped to the rod actuating means 33 will advance when the pneumatic cylinder 30 causes actuating means 33 to advance, as previously explained, and as illustrated in FIG. 3.

Rod detent mechanism 38 is fixed in place, by any suitable means, in component A of the machine. Its lower portion is provided with a bore 90, to provide suitable clearance for piston rod 70. Bore 90 is countersunk and threaded at 91, to provide a support for the threaded forward end of pneumatic cylinder 30. The upper portion of the detent mechanism 38 is provided with a structure similar to that of rod actuating means 33. More specifically, there are provided vertically spaced transverse support members 92 and 93, for supporting air clamps 94, and a suitably apertured, transverse guide bar 95. The air clamps 94 include springbiased plungers 96 engagable within notches 97 formed in the top of the rods 32. When flow of compressed air through conduits 98 to air clamps 94 is shut off, by suitable solenoid controlled valves (not shown), the plungers 96 are caused by their springs to retract from the notches 97 to the rods 32.

Thus, each guide rod 32 is provided with a pair of spaced notches 83, 97 for reception of a plunger 82, 96. By means of a suitable control system, to be explained in more detail hereinafter, one or the other of the plungers 82, 96 is engaged with its rod 32, to clamp the latter either to rod actuating means 33 or rod detent mechanism 38. When selected plungers 82 are engaged with their rods 32, those rods will advance to fixture 45 (FIG. 3, stages 2, 3) when the rod actuating mechanism 33 is advanced. This occurs because the plungers 96 are retracted from the notches 97 of the selected rods 32. However, those rods which remain clamped by their plungers 96 to the rod detent mechanism 38 do not advance with the rod actuating mechanism 33. The plungers 82 of the latter rods are retracted from their notches 83 to ensure that the nonselected rods 32 remain clamped in their retracted position.

Preferably, rods 32 are of circular cross section, and are guided slidably within suitable bores provided in the rod actuating means 33, the rod detent mechanism 38 and in support member 39 of component A of the machine (FIG. 10). To prevent angular displacement of the rods 32, which would disturb the alignment between the air clamp plungers and the notches in the rods, the rear portions of the rods 32 may be truncated at their bottoms 35 (FIGS. 10, 12). A flat, horizontal support surface 40 may be provided to engage slidably with the flattened portions 35 of rods 32, to prevent angular displacement of the latter.

The structure and operation of guide rods 20 and of actuating means 21, rod detent mechanism 26 and pneumatic cylinder 25 for rods 20 are identical to that illustrated in FIGS. 9-12.

Each new advance of probe rods 20 to the supply hopper 31 must be delayed for an interval sufficient to permit cpmpletion of the selection of the rods 20, 32 preparatory to the next delivery of tubes 18 to fixture 45. This may be accomplished by any suitable means, such as a time delay relay in the circuit (not shown) which contains the solenoid controlling pneumatic cylinder 25. More specifically, when rod actuating means 21 strikes limit switch 57, upon the return of rods 20 to their normal position (FIG. 3, stage 4), switch 57 energizes the circuit to the solenoid (not shown) for pneumatic cylinder 25, preparatory to the latter advancingthe next selection of rods 20 to hopper 31. A time delay relay (not shown) in this circuit delays the energization of the solenoid (and hence the activation of the cylinder 25) sufficiently to permit completion of the selection of rods 20, 32 by the control system for the air clamps.

Turning now to FIGS. 13-15, the structure of the tube supply hopper 31 will be described. Hopper 31 is open at the top, for feeding of tubes 18 thereto, and is provided with a plurality of stationary, uniformly spaced, vertical partitions 102. Disposed midway between each adjacent pair of partitions 102 is a vertically movable partition 103. The alternating partitions 102, 103 are parallel, and the spacing therebetween is uniform, to provide vertical slots for the reception of the tubes 18 deposited in the top of hopper 31. The vertical slots provided by the alternating partitions 102, 103 are of a width just sufficient to accomodate the reception of a single tube 18, but of a height sufficient to provide for a plurality of vertically stacked tubes, in the manner illustrated in FIG. 15.

The moveable partitions 103 are each provided with front and rear extensions 103a, 1032) which extend through elongated vertical slots 104 in the front and rear walls 105, 106 of hopper 31. The partitions 103 are reciprocated vertically, as indicated by the arrows in FIG. 15.

Reciprocatory motion is imparted to the movable partitions 103 by means of four cranks and a pair of spaced crankshafts. More particularly, secured to the upper portion of front wall 105 of hopper 31, by suitable spaced brackets 110, 111, is a rotatable, transverse crankshaft 112 on the opposite ends of which are suitably secured a pair of vertically dependent cranks 113 (FIG. 13). The lower ends of the cranks 213 are secured, in any suitable manner, to a transverse beam 114, Affixed to the beam 114, at uniformly spaced intervals, are the extensions 103a of the movable partitions 103.

Similarly, there is mounted on the rear wall 106 of hopper 31 a pair of spaced brackets 117, 118 for supporting crankshaft 119 (FIGS. 1, 14). Mounted on the opposite ends of crankshaft 119 are a pair of vertically dependent cranks 120, the lower ends of which are secured to a transverse beam 121. The protruding extensions 10317 of the vertically movable partitions 103 are affixed in uniformly spaced relation to the beam 121.

Thus, rotation of crankshafts 112, 119 imparts a vertically reciprocal movement to the several partitions 103. The effect of this motion is to provide uniform distribution, in successive horizontal layers, of the tubes 18, in supply hopper 31, as indicated schematically in FIG. 15. The slots 104 in the front and rear walls 105, 106 of hopper 31 are elongated vertically, to accommodate the vertical movement of the partition extensions 103a, 10312. The movable partitions 103 are pro vided with vertically dependent portions 1030 which extend below the floor 107 of supply hopper 31, to ensure that, at all times, the individual tubes 18 in the bottom layer of tubes remain separated. The foregoing arrangement ensures that, at all times, there is a full complement of tubes 18 in the bottom layer of tubes in hopper 31, preparatory to transfer of tubes to the fixture 45.

As best shown in FIG. 2, crankshafts 112, 119 are driven by an electric motor 125 through a suitable gear reduction unit 126 and a conventional sprocket chain and gear system 127.

Referring now to FIGS. 1, 2, 13 and 14, the detailed structure of the work table 44 and the means for imparting vertical and horizontal movement to it, now will be described. Table 44 includes a flat, horizontal plate 170 provided on its bottom with a pair of spaced, transverse, L-shaped track portions 171, 172 (FIG. 14); Spaced below plate 170 is a second flat, horizontal plate 173 having a pair of spaced, transverse, L-shaped track portions 174, 175. The track sections 171, 174 and 172, 175 are in slidably mating relationship to provide a pair of gibs, whereby upper plate 170 of table 44 may be moved transversely of the machine with respect to lower plate 173, which is secured against transverse movement.

As shown in FIGS. 1, 4, 13, 14, fixture 45 includes a bottom plate 41 on which the end plate supports 50 and the supports 48 are mounted. Support plate 41 is provided with a lateral extension 42 having a vertical bore 43. The fixture 45 is retained in position on the top of plate 170 of table 44 by means of stop plates 169 disposed on one side of fixture support plate 41 and a vertical pin 168 engaged snugly within the bore 43 of extension 42 and a co-axial hole 167 in the top of plate 170.

Affixed to the bottom of lower plate 173 adjacent each comer thereof (FIGS, 1, 13) are four dependent guide rods 176. The guide rods 176 are disposed slidably within co-axial apertures 177, 178 provided, respectively, in the horizontally spaced support plates 146, 147 of a support frame 148. This arrangement permits plates 173, 170 of work table 44 to be moved vertically up and down with respect to the stationary support frame 148.

Both horizontal and vertical movement is imparted to work table 44 by an electric motor (FIG. 2) acting through electric clutch 141, indexing unit 142 and a vertical, rotatable, output shaft 143 extending upward from the indexing unit 142. Shaft 143 is journalled in suitable bearings 144, 145 mounted, respectively, in the spaced support plates 146, 147 (FIG. 13).

Affixed to vertical shaft 143, above the top of plate 147, is a spur gear 150 which meshes with and drives a pair of spaced gears 151, 152 (FIG. 14). The driven gears 151, 152 are secured, respectively, to spaced vertical screws 153, 154 of reverse pitch, which are affixed to, and depend from, the bottom of lower plate 173 of work table 44. Thus, when output shaft 143 is driven, gear 150 drives gears 151, 152 to turn vertical screws 153, 154 to raise or lower work table 44, depending on the direction of rotation of motor 140.

Affixed adjacent the top of shaft 143, just below support 146 (FIG. 13), is a pinion 155 which meshes with and drives a gear 156 mounted on a short, vertical shaft 157. The shaft 157 is suspended from plate 173 and is journalled in a bearing 158 in plate 173, in a bearing 161 in support plate 146 and in a bearing 159 in a support 160. The support 160 may be affixed to and depend from the bottom of support plate 146 of support frame 148.

Shaft 157 is provided with an elongated, axial keyway 162 which is engagable slidably with a key affixed to and extending internally of the bore of gear 156. By reason of this construction, and by reason of being slidable axially with respect to bearings 159, 161 and gear 156, shaft 157 is free to move vertically with work table 44. Gear 156 is retained against vertical movement by the opposing surfaces of support plate 146 and support 160. The upper portion of bearing 159 in support 160 is provided with a flanged portion to provide a horizontal bearing support for gear 156.

The uppermost end of shaft 157 extends above the top of support plate 173, and has mounted thereon an eccentric 163 snuggly disposed between the opposing surfaces of a pair of spaced, vertical ribs 164 which depend from the bottom of upper plate of work table 44. The ribs 164 are disposed axially of the machine (FIG. 14) and hold the eccentric 163 captive. Thus,

when angular movement is imparted to shaft 157, by means of shaft 143 and gears 155, 156, the upper plate 170 of work table 44 is caused to move in a horizontal plane transversely of the machine, the sliding engagement of the gibs 171, 174 and 172, 175, making such movement possible, as previously explained.

Thus, motor 140, acting through electric clutch 141, indexing unit 142 and shaft 143 imparts vertical movement to work table 44 via gear 150, and imparts horizontal movement to the table via gear 155. Motor 140 runs continuously in one direction during each operative cycle of the machine, but is stopped automatically, as will be explained, upon the completion of each operative cycle. Electric clutch 141 preferably is of the one revolution" type, whereby its intermittent energization is operative for a time interval sufficient to impart one full, intermittent revolution to shaft 143.

More particularly, when limit switch 57 is activated by rod actuating means 21, upon the return of rods to their normal position (FIGS. 3, stage 4), a circuit to the electric clutch 141 is energized, thereby completing the driving connection between motor 140 and indexing unit 142. This causes shaft 143 to turn or rotate one full revolution, whereupon the clutch is de-energized to terminate the driving connection between indexing unit 142 and motor 140.

The ratio of gear 150 to driven gears 151, 152 may be 66:67, whereby gears 151, 152 rotate slightly more than one full revolution during their intermittent, angular movement, to turn screws 153, 154 either to raise or lower the work table 144, depending on the direction of rotation of shaft 143. The pitch of the threads of screws 153, 154 and the relationship of the parts is such as to ensure that work table 44 is moved vertically an incremental distance sufficient to bring the succeeding rows of apertures 51, 52 in fixture 45 into the working plane of the machine.

The eccentric 163 rests on top of lower plate 173 of table 44 and hence it, together with its dependent shaft 157, rises and falls with the vertical movement of table 44. The ratio between gears 155, 156 preferably may be 2:1, whereby gear 156, shaft 157 and eccentric 163 make one-half revolution for each complete revolution of gear 155. The upper plate 170 of work table 44 is caused by eccentric 163 to reciprocate horizontally, transversely of the machine, upon vertical movement of the work table.

The shape of the eccentric 163 is such as to cause plate 170 of work table 44 to move through one complete unidirectional reciprocatory stroke during each half revolution of shaft 157. The succeeding horizontal reciprocal strokes of plate 170 align axially the staggered apertures 51, 52 in the succeeding rows of apertures with the rods 20, 32 and the tubes 18 in the working plane of the machine, preparatory to the transfer of tubes from hopper 31 to fixture 45.

Referring next to FIGS. 1, 13, 16 and 17, the automatic controls for the machine now will be described. The controls include a plurality of microswitches 188 disposed horizontally on a fixed panel 189 supported in component B of the machine, adjacent the support frame 148 (FIG. 13). The microswitches 188 are activated selectively by successive horizontal rows of knobs, buttons or similar protuberances 190 affixed to a vertically movable control plate 191. As a comparison of FIGS. 6 and 16 illustrates, the knobs 190 correspond with the apertures 51 of the baffle plates 19.

Thus, like apertures 51, knobs are arranged in successive horizontal rows, with the knobs of adjacent rows disposed in staggered relationship to each other. For each row of apertures 51 (and 52), there is a com csponding row of knobs 90, and in the corresponding rows there are an equal number of apertures and knobs. The microswitches 188 are connected electrically to the solenoid controlled pneumatic valves (not shown) which control the flow of air to the air clamps for the rods 20, 32. Each microswitch 188 is connected to an individual circuit which includes the solenoids (not shown) for each pair of air clamps 78, 94 for each insertion rod 32 and also for each pair of air clamps (not shown) for the corresponding guide rod 20. Thus, when a particular microswitch 188 is activated by its knob 190, it activates the four solenoids of its circuit to permit compressed air to flow to the corresponding air clamps of rod actuating means 21, 33 to clamp the selected rods 20, 32 preparatory to their activation while, at the same time, shutting off flow of compressed air to the corresponding air clamps of rod detent mechanisms 26, 38, thereby permitting unclamping of those clamps from the selected rods 20, 32. Thus, the combination of the knobs 190 on control plate 191 and the microswitches 188 is operative to select, through conventional electro-pneumatic means controlling the air clamps, for each incremental process step of the machine, precisely those guide rods 20 and insertion rods 32 necessary to be activated to transfer a selection of tubes 18 from hopper 31 to fixture 45.

Control panel 191 is affixed to a vertically movable slide 192 (FIG. 13) formed with a lateral extension 193 having a vertical, threaded bore 194 therein. Threadly engaged in bore 194 is an elongated vertical screw 195.

The slide 192 dovetails in sliding engagement with a vertical guide 196 (FIG. 17 affixed to the support frame 148 of the machine. A vertical, elongated opening 197 is formed in the guide 196 for reception of the vertical screw 195. The opposite ends of screw 195 are supported rotatably in the guide 196 at each end of opening 197. Thus, screw 195 is free to turn within opening 197 to impart vertical movement to the control panel 191 through threaded bore 194. Affixed to the top of screw 195 is pinion 199 which meshes with, and is driven by, gear 156. The ratio of gear 156 topinion 199 may be l:5, so that for each half revolution made by gear 156, pinion 199 makes 2% revolutions. Thus, the intermittent rotation of shaft 143, transmitted through gears 155, 156, 199 to screw 195, imparts intermittent vertical movement to control panel 191 relative to the microswitches 188. The direction of rotation of motor 140, and hence of shaft 143, determines whether control panel moves up or down. Preferably, the arrangement is harmonized so that control panel 191 moves up when work table 44 moves up, and moves down when the table moves down.

The extent to which table 44 moves up and down, during each operative cycle of the machine, and the automatic shutting off of motor 140, upon completion of each such cycle, is controlled by spaced microswitches 204, 205 mounted adjacent control panel 191 (FIG. 13). The microswitches 204, 205 are activated, respectively, by spaced fingers 206, 207 mounted on control panel 191.

More particularly, as table 44 and control panel 191 move up to complete an assembly of tubes in fixture 45,

finger 206 approaches microswitch 204. Following the deposit of the last row of tubes in the fixture, the retraction of rod advancing means 21 activates microswitch 57 (FIG. 3, stage 4) to energize the electric clutch 141 to cause table 44 and panel 191 to move upward once again, whereupon finger 206 contracts microswitch 204, as indicated by the shadow lines in FIG. 13. This activation of switch 204 shuts off motor 140, while, at the same time, reverses its polarity so that, when the motor is started again, it will reverse its direction of rotation to cause table 44 and control panel 191 to move downward during the next operative cycle of the machine.

Similarly, as table 44 and control panel 191 move downward, to complete an assembly of tubes in fixture 45, finger 207 strikes microswitch 205, as shown by the shadow lines in FIG. 13, to shut off motor 140 and again reverse its polarity. Thus, when the motor again isstarted, it rotates in the reverse direction to move table 44 and control panel 191 upward.

Following each operative cycle of the machine, the motor 140 remains shut off, until the tube assembly 16 is removed from fixture 45, and the fixture made ready for the next assembly. Thereupon, a conventional start button (not shown) is activated to start motor 140 and re-energize the circuits of the machine, for its next operative cycle.

The electrical circuitry of the machine is of conventional design, as are the various microswitches, solenoid actuated air valves (not shown), time delay relays (not shown), etc. employed therein, and form no part of this invention.

Although a preferred embodiment of this invention has been shown and described for the purpose of illustration, it is to be understood that various changes and modifications may be made therein without the parting from the spirit and utility of the invention, or the scope thereof as set forth in the appended claims.

We claim:

1. A machine for assembling automatically the tubes for a heat exchanger having a plurality of tubes and perforated baffle plates, said machine comprising:

1. a work table having capacity for vertical and horizontal movement,

2. a tube holding fixture mounted on the table, said fixture having:

a. a pair of spaced, co-axial, perforated end plates, the respective perforations of which are disposed in successive rows, with each perforation of each end plate co-axial with a corresponding perforation in the other end plate, and

b. at least one intermediate baffle plate supporting means,

c. said baffle plate supporting means being operative to support perforated baffle plates with their perforations aligned axially with co-axial perforations of the end plates,

3. a tube supply adjacent to the tabie,

4. means associated with the tube supply for maintaining the tubes in successive horizontal layers,

5. a first plurality of horizontally disposed rods,

6. a second plurality of horizontally disposed rods,

7. said two sets of rods being mounted on opposite sides of the tube supply and having their individual rods aligned axially with corresponding rods of the other set,

8. means for actuating a selected quantity of rods of each set of rods to advance the same to thetube supply to withdraw therefrom a selected quantity of tubes and deposit said tubes in the fixture within axially aligned perforations,

9. control means for selecting a pre-determined quantity of rods of each set of rods preparatory to advancing the rods of the tube supply, and

10. table actuating means for changing automatically the position of the table relative to the tube supply following each successive deposit of tubes in the fixture.

2. A machine .for assembling tubes for a heat exchanger comprising:

1. a table,

2. a tube holding fixture mounted on the table,

3. a tube supply adjacent to the table,

4. tube advancing means for advancing successively a selected quantity of tubes from the tube supply to the fixture, and

5. table actuating means for changing automatically the position of the table relative to the tube supply following each successive advance of tubes from the tube supply to the fixture, preparatory to the next advance of tubes to the fixture.

3. The machine of claim 2 wherein the tube advancing means comprises:

i. a first set of axially advanceable and retractable rods, and

2. a second set of axially advanceable and retractable rods,

3. said two sets of rods being disposed on opposite sides of the tube supply when in their most retracted position,

4. said two sets of rods being operative to advance selectively to the tube supply, withdraw a selected quantity of tubes therefrom and deposit the same in the tube holding fixture.

4. The machine of claim 3 wherein:

l. the rods of both sets of rods and at least some tubes of the tube supply are disposed in a common working plane of the machine,

2. the fixtures is provided with:

a. a pair of spaced, co-axial, perforated end plates, the respective perforations of which are disposed in successive rows, with each perforation of each end plate co-axial with a corresponding perforation in the other end plate, and

b. one or more intermediate baffle plate supporting means,

c. said baffle plate supporting means being operative to support perforated baffe plates with their perforations aligned axially with co-axial perforations of the end plates, and

3. the table actuating means is operative automatically to position successive rows of said perforations in the working plane preparatory to each advance of tubes to the fixture.

5. The machine of claim 3 wherein rods of the first set of rods are aligned axially with rods of the second set.

6. The machine of claim 3 wherein:

i. each set of rods is disposed horizontally and 2. the table actuating means is operative to move the table vertically relative to the tube supply and the two sets of rods.

7. The machine of claim 6 further including means associated with the tube supply to maintain the tubes in successive horizontal layers.

8. The machine of claim 3 further including:

1. control means for selecting a pre-determined quantity of rods of each set of rods preparatory to advancing a selected quantity of tubes from the tube supply to the fixture following each movement of the table, and

2. rod actuating means for advancing the selected rods to and retracting said rods from the tube supply.

9. The machine of claim 8 wherein the fixture,

1. has a pair of spaced, co-axial, perforated end plates, the perforations of each plate being aligned axially with corresponding perforations of the other plate, and

2. includes one or more intermediate baffle plate supporting means,

3. said baffle plate supporting means being operative to support perforated baffle plates with their perforations aligned axially with co-axial perforations of the end plates.

10. The machine of claim 9, wherein:

l. the rods of the two sets of rods are all disposed in the same axial plane,

2. the perforations of each fixture end plate are disposed in a plurality of successive co-planar rows and 3. the table actuating means is operative to position successive rows of perforations of both end plates in co-planar alignment with the two sets of rods, with one perforation of each co-planar row co-axial with one rod of each set of rods,

4. whereby, upon the advance of a selected quantity of tubes from the tube supply, said tubes are deposited in the fixture within axially aligned perforations.

11. The machine of claim 9 wherein:

l. the rods of both sets of rods and at least some of the tubes in the tube supply are disposed in a single working plane of the machine,

2. the perforations of each fixture end plate are disposed in a plurality of successive co-planar rows, and 3. the table actuating means, following each advance of tubes from the tube supply to the fixture, is operative automatically to move the table to locate the next successive co-planar rows of perforations of the fixture end plates in the working plane.

12. A machine for assembling automatically the tubes for a shell and tube type heat exchanger comprising:

1. a movable work table,

2. a perforated fixture mounted on the table,

3. a supply of tubes spaced from the fixture,

4. a plurality of individually controlled tube transfer devices for transmitting selected quanities fo tubes from the supply to the fixture for deposit within selected perforations in the fixture,

5. adjustment means for adjusting the table relative to the tube supply prior to each transmission of tubes to the fixture to position a selected quantity of perforations for reception of a selected quantity of transmitted tubes, and

6. actuating means for actuating selected quantities of the tube transfer devices in timed relation to each adjustment of the table.

13. The machine of claim 12 wherein:

l. the supply of tubes and the tube transfer devices are located in a common working plane of the machine, and

2. the table adjustment means positions a selected quantity of fixture perforations in the working plane prior to each transmission of tubes to the fixture.

14. A tube holding fixture for a machine for assembling tubes for a heat exchanger comprising:

1. a pair of spaced, co-axial, perforated end plates, the respective perforations of which are disposed in successive rows, with each perforation of each end plate co-axial with a corresponding perforation in the other end plate, and I 2. at least one baffle plate support intermediate the end plates having a hinged member to permit insertion, clamping and removal of a baffle plate,

3. said baffle plate support being operative to support perforated baffle plates with their perforations aligned axially with co-axial perforations of the end plates.

UfiiTED STATES" CERTIFICATE OF CORRECTION Patent No. 9 I Dated Febrfiary zs", 19-74 v Morton F. Ziffe'rei: and Ddnald E. Flinchbaligh Inventor(s) v v i v It is certified that error appears the 'b eve-idenfifi ed, fietent and that said Letters Patent are hereby corrected as shown be l oy:

Column 1, line 40 "steps" should be st a' ges- I Celumnf4fline 6 2" 2 2 's hqu ld be +20 I C lumn- '5, lir ie 17 after piston in se rvt Column 6 line 'l1 o" b e' -df--:. -f N I Column 14, line l lf'ofw is misspelled;-

signed a d: sealed th sfzachfday b1:-

(SEAL)- Attest: e MccdY M." cmsbN JRQfif I f L I C V Attesting Officer; I cqmisnonefrof iz l e teht's FORM Po-1o5o (10-69)v 

1. A machine for assembling automatically the tubes for a heat exchanger having a plurality of tubes and perforated baffle plates, said machine comprising:
 1. a work table having capacity for vertical and horizontal movement,
 2. a tube holding fixture mounted on the table, said fixture having: a. a pair of spaced, co-axial, perforated end plates, the respective perforations of which are disposed in successive rows, with each perforation of each end plate co-axial with a corresponding perforation in the other end plate, and b. at least one intermediate baffle plate supporting means, c. said baffle plate supporting means being operative to support perforated baffle plates with their perforations aligned axially with co-axial perforations of the end plates,
 3. a tube supply adjacent to the table,
 4. means associated with the tube supply for maintaining the tubes in successive horizontal layers,
 5. a first plurality of horizontally disposed rods,
 6. a second plurality of horizontally disposed rods,
 7. said two sets of rods being mounted on opposite sides of the tube supply and having their individual rods aligned axially with corresponding rods of the other set,
 8. means for actuating a selected quantity of rods of each set of rods to advance the same to the tube supply to withdraw therefrom a selected quantity of tubes and deposit said tubes in the fixture within axially aligned perforations,
 9. control means for selecting a pre-determined quantity of rods of each set of rods preparatory to advancing the rods of the tube supply, and
 10. table actuating means for changing automatically the position of the table relative to the tube supply following each successive deposit of tubes in the fixture.
 2. a tube holding fixture mounted on the table, said fixture having: a. a pair of spaced, co-axial, perforated end plates, the respective perforations of which are disposed in successive rows, with each perforation of each end plate co-axial with a corresponding perforation in the other end plate, and b. at least one intermediate baffle plate supporting means, c. said baffle plate supporting means being operative to support perforated baffle plates with their perforations aligned axially with co-axial perforations of the end plates,
 2. A machine for assembling tubes for a heat exchanger comprising:
 2. a tube holding fixture mounted on the table,
 2. a second set of axially advanceable and retractable rods,
 2. the fixtures is provided with: a. a pair of spaced, co-axial, perforated end plates, the respective perforations of which are disposed in successive rows, with each perforation of each end plate co-axial with a corresponding perforation in the other end plate, and b. one or more intermediate baffle plate supporting means, c. said baffle plate supporting means being operative to support perforated baffe plates with their perforations aligned axially with co-axial perforations of the end plates, and
 2. the table actuating means is operative to move the table vertically relative to the tube supply and the two sets of rods.
 2. a perforated fixture mounted on the table,
 2. rod actuating means for advancing the selected rods to and retracting said rods from the tube supply.
 2. the perforations of each fixture end plate are disposed in a plurality of successive co-planar rows, and
 3. the table actuating means, following each advance of tubes from the tube supply to the fixture, is operative automatically to move the table to locate the next successive co-planar rows of perforations of the fixture end plates in the working plane.
 2. at least one baffle plate support intermediate the end plates having a hinged member to permit insertion, clamping and removal of a baffle plate,
 2. the table adjustment means positions a selected quantity of fixture perforations in the working plane prior to each transmission of tubes to the fixture.
 2. the perforations of each fixture end plate are disposed in a plurality of successive co-planar rows and
 2. includes one or more intermediate baffle plate supporting means,
 3. said baffle plate supporting means being operative to support perforated baffle plates with their perforations aligned axially with co-axial perforations of the end plates.
 3. a supply of tubes spaced from the fixture,
 3. the table actuating means is operative to position successive rows of perforations of both end plates in co-planar alignment with the two sets of rods, with one perforation of each co-planar row co-axial with one rod of each set of rods,
 3. said baffle plate support being operative to support perforated baffle plates with their perforations aligned axially with co-axial perforations of the end plates.
 3. The machine of claim 2 wherein the tube advancing means comprises:
 3. the table actuating means is operative automatically to position successive rows of said perforations in the working plane preparatory to each advance of tubes to the fixture.
 3. said two sets of rods being disposed on opposite sides of the tube supply when in their most retracted position,
 3. a tube supply adjacent to the table,
 3. a tube supply adjacent to the table,
 4. means associated with the tube supply for maintaining the tubes in successive horizontal layers,
 4. tube advancing means for advancing successively a selected quantity of tubes from the tube supply to the fixture, and
 4. said two sets of rods being operative to advance selectively to the tube supply, withdraw a selected quantity of tubes therefrom and deposit the same in the tube holding fixture.
 4. The machine of claim 3 wherein:
 4. whereby, upon the advance of a selected quantity of tubes from the tube supply, said tubes are deposited in the fixture within axially aligned perforations.
 4. a plurality of individually controlled tube transfer devices for transmitting selected quanities fo tubes from the supply to the fixture for deposit within selected perforations in the fixture,
 5. adjustment means for adjusting the table relative to the tube supply prior to each transmission of tubes to the fixture to position a selected quantity of perforations for reception of a selected quantity of transmitted tubes, and
 5. The machine of claim 3 wherein rods of the first set of rods are aligned axially with rods of the second set.
 5. table actuating means for changing automatically the position of the table relative to the tube supply following each successive advance of tubes from the tube supply to the fixture, preparatory to the next advance of tubes to the fixture.
 5. a first plurality of horizontally disposed rods,
 6. a second plurality of horizontally disposed rods,
 6. The machine of claim 3 wherein:
 6. actuating means for actuating selected quantities of the tube transfer devices in timed relation to each adjustment of the table.
 7. The machine of claim 6 further including means associated with the tube supply to maintain the tubes in successive horizontal layers.
 7. said two sets of rods being mounted on opposite sides of the tube supply and having their individual rods aligned axially with corresponding rods of the other set,
 8. means for actuating a selected quantity of rods of each set of rods to advance the same to the tube supply to withdraw therefrom a selected quantity of tubes and deposit said tubes in the fixture within axially aligned perforations,
 8. The machine of claim 3 further including:
 9. control means for selecting a pre-determined quantity of rods of each set of rods preparatory to advancing the rods of the tube supply, and
 9. The machine of claim 8 wherein the fixture,
 10. The machine of claim 9, wherein:
 10. table actuating means for changing automatically the position of the table relative to the tube supply following each successive deposit of tubes in the fixture.
 11. The machine of claim 9 wherein:
 12. A machine for assembling automatically the tubes for a shell and tube type heat exchanGer comprising:
 13. The machine of claim 12 wherein:
 14. A tube holding fixture for a machine for assembling tubes for a heat exchanger comprising: 